| 1. |
- Edner, Hans, et al.
(författare)
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Lidar measurements of atmospheric mercury
- 1990
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Ingår i: Environment and Pollution Measurement Sensors and Systems. - : SPIE. ; 1269:1, s. 73-80
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Konferensbidrag (refereegranskat)
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| 2. |
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| 3. |
- Axelsson, H, et al.
(författare)
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Differential Optical Absorption Spectroscopy (DOAS) Measurements of Ozone in the 280--290 nm Wavelength Region
- 1990
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Ingår i: Applied Spectroscopy. - : SAGE Publications. - 1943-3530 .- 0003-7028. ; 44:10, s. 1654-1658
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Tidskriftsartikel (refereegranskat)abstract
- The differential absorption structure of the ozone spectrum between 250 and 330 nm has been investigated in order to determine the optimal wavelength region to be utilized for active differential optical absorption spectroscopy (DOAS) measurements. Considering aspects of atmospheric attenuation and interference from other species as well as the magnitude of the differential absorption cross section, an interval around 283 nm was found to be a good candidate for this application. This result was also verified during 12 months of continuous ozone monitoring in an urban environment.
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| 4. |
- Axelsson, H, et al.
(författare)
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Measurement of Aromatic-hydrocarbons With the DOAS Technique
- 1995
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Ingår i: Applied Spectroscopy. - : SAGE Publications. - 1943-3530 .- 0003-7028. ; 49:9, s. 1254-1260
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Tidskriftsartikel (refereegranskat)abstract
- Long-path DOAS (differential optical absorption spectroscopy) in the ultraviolet spectral region has been shown to be applicable for low-concentration measurements of light aromatic hydrocarbons. However, because of spectral interferences among different aromatics as well as with oxygen, ozone, and sulfur dioxide, the application of the DOAS technique for this group of components is not without problems. This project includes a study of the differential absorption characteristics, between 250 and 280 nm, of twelve light aromatic hydrocarbons representing major constituents in technical solvents used in the automobile industry. Spectral overlapping between the different species, including oxygen, ozone, and sulfur dioxide, has been investigated and related to the chemical structure of the different aromatics. Interference effects in the DOAS application due to spectral overlapping have been investigated both in quantitative and in qualitative terms, with data from a field campaign at a major automobile manufacturing plant.
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| 5. |
- Axelsson, Håkan, et al.
(författare)
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Mätning av aromatiska kolväten med DOAS. En studie av tillförlitlighets- och interferensproblem.
- 1990
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- DOAS-tekniken är en optisk fjärranalysmetod för mätning av luftföroreningar. I det projekt som här avrapporterats har tekniken utvärderats m a p mätning av lätta aromatiska kolväten. Projektet har omfattat såväl litteratur, labb och fältstudier av absorptionsegenskaper som interferenseffekter. Resultaten visar att de lätta aromatiska kolväten har ett gemensamt absorptionsband i nära UV (250-280 mm ) som med fördel kan användas i en DOAS-tillämpning. Utnyttjande detta band, kan flera av aromaterna mätas med en detektionsgräns på några µg/m3. Dock föreligger kraftiga interferenseffekter mellan i synnerhet komponenter med likartad kemisk struktur. Detta problem kan i vissa fall hanteras m h a multipel regressions analys. En förutsättning för detta är dock att inga 'okända' interferande ämnen (lös aromater) förekommer i mätsituationen.
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| 6. |
- Bengtsson, Magnus, et al.
(författare)
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Lidar fluorescence measurements of algal growth on electrical insulators
- 2003
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Ingår i: 2003 Conference on Lasers and Electro-Optics Europe (CLEO/Europe 2003) (IEEE Cat. No.03TH8666). - 0780377346 ; , s. 473-473
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Konferensbidrag (refereegranskat)abstract
- Fluorescence measurements using lidar techniques have been shown to be useful for monitoring of algal growth on e.g. historical monuments. In this experiment similar measurements were performed on electrical insulators to examine the correlation between algal growth and the quality of the insulator, a factor of importance in the high-voltage grid management
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| 7. |
- Bennett, M, et al.
(författare)
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Joint application of Doppler Lidar and differential absorption lidar to estimate the atomic mercury flux from a chlor-alkali plant
- 2006
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Ingår i: Atmospheric Environment. - : Elsevier BV. - 1352-2310. ; 40:4, s. 664-673
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Tidskriftsartikel (refereegranskat)abstract
- We have combined differential absorption lidar (DIAL) measurements of mercury concentrations downwind of a chloralkali plant (Rosignano Solvay) with measurements of wind profiles made with a Doppler Lidar based on modern fibreoptic technology. Since the flux of pollutant is equal to the cross-wind integral of the product of concentration and wind speed, this should permit us to make a more precise estimate of the fugitive emission of mercury from the plant than could be obtained by using anemometer measurements of the wind. The flux was estimated to be 54g Hgh(-1) using an anemometer on the plant building; 49g Hgh(-1) using an anemometer on a nearby 10m mast; and 48g Hgh(-1) using wind speed corrections estimated from the Doppler Lidar measurements. Because of difficulties with the range resolution of the Doppler Lidar, the precision of this estimate was not as good as it should have been, though the difference from the rooftop anemometer remains statistically significant. Corrections of this magnitude are irrelevant to the Rosignano plant, where the emission rate varies strongly with the meteorological conditions. Where a precise estimate of a steady flux is required, however, reliable measurements of the wind profile in the wake of the source are essential. Doppler Lidar provides a possible method for acquiring such measurements. (c) 2005 Elsevier Ltd. All rights reserved.
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| 8. |
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| 9. |
- Dernfalk, Andreas, 1975, et al.
(författare)
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Laser-induced fluorescence spectroscopy for detection of biological contamination on composite insulators
- 2003
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Ingår i: In Proc. 13th International Symposium on High Voltage Engineering, Delft, Netherlands.
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Konferensbidrag (refereegranskat)abstract
- A new technique for remote detection of biological contamination on high-voltage outdoor insulators has been investigated. The technique, which is based on laser-induced fluorescence (LIF) spectroscopy, has been applied to study surfaces of real silicon rubber insulators from a distance of approximately 60 m. Measurements were performed outdoors on a number of clean, as well as, biologically contaminated insulators. Several types of biological contamination were included, as five of the studied insulators had become covered when installed in Sweden, and another three had been contaminated by fungal growth in laboratory. Fluorescence spectra obtained from the surfaces of the described insulators are presented and the applicability of the technique is discussed and compared with photographic methods.
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| 10. |
- Edner, Anna, et al.
(författare)
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Does a magnetic blanket induce changes in muscular blood flow, skin temperature and muscular tension in horses?
- 2015
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Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 47:3, s. 302-307
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Tidskriftsartikel (refereegranskat)abstract
- Reasons for performing studyStatic magnetic blankets are often claimed to induce increases in blood flow, reduce muscle tension and tenderness, and be beneficial in both prevention and treatment of musculoskeletal injuries in horses. However, there are no studies that confirm alleged beneficial effects of magnets on muscles of the back in healthy horses. ObjectivesTo investigate whether static magnets sewn into a blanket affect back muscle blood flow, skin temperature, mechanical nociceptive threshold (MNT) and behaviour in healthy horses. Study designProspective, randomised, blinded, placebo-controlled crossover study. MethodsThe following outcome measurements of the back of 10 healthy horses were performed; blood flow by photoplethysmography, skin temperature by use of thermistors in conjunction with digital infrared thermography, and MNTs by algometry. The horses behaviour was filmed during the procedure and scored on an ethogram. Measurements were performed repeatedly for a 30min baseline period. Thereafter a blanket with active, static magnets (900 gauss) or placebo magnets was placed on the horse and measurements were performed for a 60min treatment period and a 30min post treatment period. The study procedure was repeated on the consecutive day, when the horse received the alternative treatment. ResultsBlood flow in muscle, skin temperatures, MNTs and behavioural traits did not differ between active and placebo magnetic blankets. Skin temperature increased similarly during both active and placebo blanket treatment. ConclusionsIn healthy horses, magnetic blankets did not induce additional significant effects on muscle blood flow, skin temperature, MNTs and behaviour when compared with nonmagnetic blankets.
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